Harpin处理结合羧甲基壳聚糖/海藻酸钠复合涂膜对哈密瓜保鲜效果的影响

Effect of Harpin Treatment Combined with Carboxymethyl Chitosan-alginate Composite Coating on Hami Melon Preservation

摘要:

为了探讨采后Harpin诱导处理结合羧甲基壳聚糖、海藻酸钠复合涂膜相对于单独的复合涂膜对哈密瓜的保鲜效果是否有提高，在常温条件下（19±2 ℃），用浓度为90 mg/L的Harpin浸泡哈密瓜3 min，再用0.5%羧甲基壳聚糖，1%海藻酸钠，0.5%甘油，0.6%吐温80和0.5%肉桂醛复配而成的复合涂膜剂涂膜处理.以仅复合涂膜处理的哈密瓜做对比；以不处理组作空白对照。通过测定哈密瓜的维生素C，硬度，过氧化物酶（POD），丙二醛（MDA），以及霉菌和酵母菌总数，电子鼻等指标对哈密瓜进行品质评价。试验结果表明，与复合涂膜组相比，Harpin诱导结合复合涂膜处理能够减少Vc流失，保持果实硬度，有效的抑制MDA含量升高，且使哈密瓜气味产生变化，但对POD活性的提高效果以及对果肉中霉菌和酵母菌含量的抑制效果并不显著（P>0.05）。Harpin诱导结合复合涂膜比仅用涂膜处理保鲜效果更好，能延迟哈密瓜的贮藏期。

Abstract:

The effect of harpin treatment combined with a carboxymethyl chitosan-sodium alginate composite coating on Hami melon preservation was compared with that of the composite coating alone. At room temperature (19 ± 2 ℃), Hami melons were immersed in 90 mg/L harpin for three minutes and coated with a composite coating agent composed of 0.5% carboxymethyl chitosan, 1% sodium alginate, 0.5% glycerol, 0.6% Tween 80, and 0.5% cinnamic aldehyde. Hami melons treated with the composite coating alone were used as the controls, and untreated Hami melons were used as the blank controls. The quality of Hami melon was evaluated based on Vc content, firmness, peroxidase (POD) activity, malondialdehyde (MAD), total yeast and mold counts, and electronic nose results. The composite coating combined with harpin treatment resulted in a reduced loss of Vc, a similar firmness, an effectively inhibited increase in MAD, and a different scent compared with that of the composite coating group. However, the effects of harpin treatment on POD activity and the inhibition of yeast and mold in pulp did not differ significantly among groups (P > 0.05). The harpin treatment combined with carboxymethyl chitosan-alginate composite coating had a better effect on preservation than did the control group and extended the storage life of Hami melon.